Db9 Connectors - Comtrol DeviceMaster DM-2000 Series Installation And Configuration Manual

Connecting Serial Devices

DB9 Connectors

This subsection provides the following information:
• Connector pin assignments (below)
• DB9 Null-Modem Cables (RS-232)
• DB9 Null-Modem Cables (RS-422)
• DB9 Straight-Through Cables (RS-232/485)
• DB9 Loopback Plugs
• Connecting DB9 Serial Devices
Pin
1 DCD
2 RxD
3 TxD
4 DTR
5 Signal GND
6 DSR
7 RTS
8 CTS
9 RI
† The following models support RS-485 full-duplex:
• 1-Port DIN rail models
• 2-Port DIN rail models
• 4-Port DIN rail models
Note: The DeviceMaster Serial Hub only supports RS-232.
Refer to the hardware manufacturer's installation documentation if you need help with connector pin outs or
cabling for the serial device. This illustrates the DB9 connector signals.
RS-232
GND
DTR
TxD
RxD
CD
Pin 1
DB9 Male
88 - Connecting Serial Devices
on Page 89
on Page 89
on Page 90
on Page 90
DB9 Connector Pin Outs
RS-422 and RS-485 Full-Duplex
RS-232
Not used
RxD-
TxD-
Not used
Signal GND
Not used
TxD+
RxD+
Not used
GND
RI
Not used
CTS
TxD-
RTS
RxD-
DSR
Not used
Pin 6
Pin 1
DB9 Male
on Page 89
(Master/Slave)†
RS-422
GND
Not used
Not used
RxD+
TRxD-
TxD+
Not used
Not used
Not used
Pin 6
Pin 1
DeviceMaster Installation and Configuration Guide: 2000594 Rev. F
RS-485
Half-Duplex
Not used
Not used
TRxD-
Not used
Signal GND
Not used
TRxD+
Not used
Not Used
RS-485
Not used
Not used
TRxD+
Not used
Pin 6
DB9 Male